Apparatus for removing bark from logs



June 25, 1 F. A. NICHOLSON ET AL 9 I APPARATUS FOR REMOVING BARK FROMLOGS Filed Aug. 7, 1955 e Sheets-Sheet 1 r8 .mmvroxa:

reaer/ A/K/a/M/mn 5 BR mYmaf Z'Hv/abara ATTORNEY June 25, 1935. F. A.NICHOLSON El AL A 2,005,799

APPARATUS FOR REMOVING BARK FROM LOGS Filed Aug. '7, 1 6 Sheets-Sheet 2June 1935- F. A NICHOLSON ET AL 2,005,799

APPARATUS FOR REMOVING BARK FROM LOGS ATTORNEY June 25, 1935- F. A.NICHOLSON ET AL APPARATUS FOR REMOVING BARK FROM LOGS Filed Au '7 1955 6Sheets-$11661; 4

m/mal TP/ c/vard BY A TTORNEY June 25, 1935.

F. Av NICHOLSON ET AL 2,005,799

v APPARATUS FOR REMOVING BARK FROM LOGS Filed Aug. '7, 1933 6Sheets-Sheet 5 1 Fly. 6;

llllllllll 1,

A TTORNEY.

June 5, 1935- F. A. NICHOLSON ET AL 2,005,799

APPARATUS FOR REMOVING BARK FROM LOGS Filed Aug. '7, 1933 6 Sheets-Sheet6 A TTORNEY Patented June 25,

knives to'beproperly positioned to APPARATUS FOR REMOVING BARK I momLOGS Frederick A. Nicholson and Wilmot 'r. Prltchard,

Seattle, Wash, assignors to Stetson-Ross Ma- I I chineCompanma'corporation 'of Washington Application August a, 1933,Serlallilo. 684,036 l 9 claims. (01. 144-208) In connection with themaking of wood pulp intended for manufactureinto-paper for newspaper orother uses it is essential that all bark on the logs fro'm'which thematerial is obtained be completely removed.

' Prior to such removal, however, it is customary to divide the logslongitudinally into a plurality of sections in order to discover andwholly remove that are so frequently found at or adjacent to the centralpart of a log, for such rotten wood, like bark, if carried intothe'digester with the sound pieces of wood will result in an inferiorpulp product.

This invention relates to improvements in apparatus for"barking, as theact of removing the bark from logs is termed, and one of the lead-,- ingobjects of the invention is, broadly stated, the provision of novelmeans for supporting and adlusting to various operative positions arotative cutter-headso as to adapt its curved surface and thecorrespondingly curved cutting edges of. the,

knives carried thereby to conform as closely as possible to the logssurface from which the bark is to be removed, thereby, through the greatflexibility of movement of such cutter-head, permitting it to beinstantly changed inpositlon to adapt it to operatively engage logsections of different sizes and that consequently have quite widelyvarying bark surfaces, and al'sopermitting it to be so changed as toequally well adapt its engage the bark surface of a log section evenwhen such log section, by reason'of its shape, has to be so arranged onthe carrying and forwarding means that its curved bark surface cannot bepresented, even approximately, in an exposed uppermost position but willhave to lie so that such surface, during the entire barking operation,will constitute to a very large extent'a side portion of the logsection. This flexibility of adjustment of the'cutter-head to widelyvarying operative positions also results in the prevention of cuttingaway to any material extent the solid wood or body portion that isrequired for the making of the pulp.

Another important f'object ofthe invention is to so construct andarrange the devices that hold and move forward the l'og'se'ction intoposition to be acted upon by the, cutter-head that they will at alltimes 'cause the bark surface of such log section to so lie that itwill, to quite alarge-extent, constitute a lateral surface of thesaid'section, thus keeping such log section in a position that willenable the operator of the machine to more easily observe the operationof the cutterall rotten portions head and consequently be the betterable, through the controlling means attached to the machine, toinstantly shift the position of the cutter-head from time to time as isfrequently necessary to adapt it to varying conditions.

These and other objects'that will baseman later herein areattained bythe construction and arrangement of parts as shown in thedrawings andhereinafter particularly. described. That which is believed tube theclaims.

In'the drawings: r V

Fig. 1 is a side elevation of the machine with a logsection in" placeand showing that portionof such section at the right hand side of thefigure 15 denuded ofits bark by the cutter-head under which it hadpassed. Fig. 2 is a vertical cross-section taken on line 2-2 of Fig. 1,the pressure roll at the right handside of- Fig. 1 beingomitted. 1

Fig."3 is a vertical cross-section taken substantially on line 3-3 ofFig. 1, and showing the relative arrangement of the stationary frame.members, the sliding frame movable thereon and the rotatable annularframe .member that. is supported by said sliding frame, and by themovements of which sliding and rotatableparts certain of the necessaryadjustments of the cutter-head are effected.

Fig. 4-is asection taken substantialy on the line 4-4 of'Fig. 3, certainelements being omitted to better show the-relative arrangement'of thesliding, frame and the rotatable annular frame, a log section partlydenuded of its bark being shown in dotted lines. J 7

Fig; 5 is a detail showing partly in elevation and partly in verticalsection the rotary cutterhead, its driving motor and a portion of themechanism by'which it is adiustably supported.

Fig. 6 is a vertical section taken on the .line 6-6of'Fig. 5.

Fig. 7 is a view pa tly in plan and-partly in section showing therotatable annular member from which the cutter-head is supported and themeans through which thepivotal turning of' the cutter-head isaccomplished.

Fig. 8 is a'de'tail, partlyin vertical section, iilustrating therelative arrangement of. one of the pairs of toothed rollers that coactto move newrwill be set forth in diameter than that shown in Fig. lgandshowing such larger log sawed into sections of different shapes.

Fig. 12 is a detached end view of one of the quarter sections of the logof Fig. 10, and canted laterally as it would be while moving through themachine.

Figs. 13 and 14 are diagrammatic views illustrating different positionsto which the cutterhead can be adjusted by the operator to bring theknives thereof into positions to effectively engage the bark surface ofa log section.

Referring to the several figures of the drawings in which correspondingparts are indicated by the same reference characters,-2i l indicateslongitudinally-extending base members that have: I i fast onthe shaft 23-or.- 24. The two aligned I mounted upon them a heavy'frame designatedgenerally by the reference numeral 2|. .This frame is made in twoseparated units as clear- 1y shown in Fig. 1, said units being in linewith each other, of course, and held in' alignment by their connectionwith the longitudinalbase member: 20, 20. Further connection of theseframe units to each other is by means of a trough-like member 35 thatbridges the gap between the units and also serves as a guiding supportfor logsections that are longitudinally moved through the machine ashereinafter described. One-end of this bridging member 35, in theconstruction shown, is supported by a bracket 36 to which it is boltedand the other end is bolted to aheavy supporting member :thatishereinafter referred to. This bridging piece 25' is ofthe same The ofmovement of certain parts as hereinafter will Extending along one sideof each of the frame units 2| and bolted or otherwise secured thereto isa housing 22,- in each of whichis journaled a shaft, the shaft in thehousing onthe logreceiving end (the one at the left handin Fig. l) ofthe machinebeing indicated by 23 and the other shaft on the log-deliveryend being indicated by 24. In connection-with each frame unit 2|thereare provided a plurality of, pairs of toothed rollers 25, 25" whosefunction is twofold, viz. to furnish a supportfor the log sections torest upon as they pass through the machine andalso by their continuedrotation to cause the desired movement of the said sections.

As best shown in Figs. 2 and 8 the rollers of each pair are at an angleto each other of approximately 90 degrees. The rollers of eachpair arenot inclined to the same extent, but are preferably so arranged that oneof them is inclined to about 20 degrees from the horizontal while theother is inclined in the opposite direction to stand at about twentydegrees from the vertical. So arranged it will be evident that. a logsection, whether of the shape of that section that is shown on therollers in Figs. 2 and 8 or of the character of any'of the sectionsshown in Figs. 10 and 11, and indicated by reference letters A, B, C,D,E, F and G, respectively, will so rest on the rollers that the barksurface will be presented largely toward one side of the machine. Thislateral presentation of such surface, thus designedly obtained, is ofvery considerable importance. as it thus presents to the attendant amuch better and more complete view of the bark surface than could beattained if the pair of rollers were inclined in opposite directions atthe same angle. This will be apparent from Fig. 2 where it will be seenthat controls at which the operator is stationed are'at that side of themachine towards which the rollers 25 project. These various pairs ofrollers are all arranged in the same manner and together constitute ineffect a trough-like table for feeding the log sections through themachine.

Each roller has a shaft, designated by 29, to

which it is made fast." The upper end of each shaft is journaled in asuitable bearing 26 carriedby the frame and the lower portion of eachshaft projects into the housing 22 (see Fig. 2) and is there supportedby a bearing aiiixed to said housing. On the lower end of each shaft issecured a spiral gear. 28, and meshing with the gears 28 of each pairisa spiralgear 21 that is shafts 23, 24 are to be. so connected togetheras to rotate uniformly. As here. illustrated such 7 driving is attainedthrough -a countershaft 30 that is arranged adjacent, to one of the baseframe membersv 20 and drive chains 3|; that engage sprocket wheels .onthat countershaft and on the alignedshafts 23, 24.

To hold the log sections down firmly so as to ensure of their beingproperly engagedand moved by the rotating toothed rollers pressure rolls32. are provided over .thepath of travel of the log sections, two ofsuch rolls, in theconstruction shown, beingprovided in connection witheachof the frame units 2 I. Theaxle or shaft on which each of suchrolls-turns is pivotally connected with the free end .of a link 34 theother end of which is pivoted to an arched support 33.as clear-' 1yvshown in Fig. 8.

Extending transversely and located inthe gap between the twoframe units2| and adjacent, in the construction illustrated, to the irmer end ofthe log delivery unit is a heavy frame 40 de-' signed to aflord supportfor the cutter-head and the adjustable elements that areconnectedtherewith. The main or body portion of this supporting frame 40necessarily lies well below the path of travel of the log sections butfrom such body portion extend at an angle. of approximately. fortydegrees two heavy arms 40, these arms extending up at opposite sides ofthe machine. Upon, eachof these diagonal arms is formed alongitudinally-extending strip or rib 4|, said strips or ribs acting asguides for a movable frame that is located between said arms 40".

The movable frame just referred to and that is adapted to have slidingengagement with the said inclined arms .comprisesa cross-head .42, andtwo arms 43 that have sliding engagement with the diagonal frame arms511 and are held in such sliding engagement by suitable retaining strips45. Formed with or fixedly secured to'the slide arms 43 is an annulus 44that is provided for the purpose of affording a bearing for therotatable ring-like support that carries the'adjustable cutter-head..The sliding movements or this frame thatcomprises the parts 42, 43 and44 are accomplished through the rotation of a threaded shaft 46 thatsuitably engages the cross-head member 42, said shaft having powerapplied to it through an ordinary reversible air as hereinafter referredto.

lus 44 of the sliding frame device is a rotatable motor 41:

ring-like member 48 that has attached to it the cutter-head that isemployed for theremoval of the bark-from the log. sections. 1 11115cutter-1 head supporting member 48 is ,held, in place by a ring 58bolted to the annulus 44 of the slid.-

ing member and projecting past aflange 48 on the rotatable member 48.The'rot'ation of this ring-like member 48 is ..needed to be madethroughonly'a comparatively small arc and is required for. themaking of one ofthe several adjustments of the cutter-head, as will befully "The saidpinion 53 projects through an opening in this guard strip as clearlyshown in Fig. 3.

The pinion 53 is fast on a short shaft 54 near one end thereof andadjacentto the other end of such shaft is secured a spiral gear 55 thatis in constant engagement with a spiral gear 55 that is mounted on aninclined shaft 51- and slidp ter-head have their projecting cuttingedges ably held thereon by its engagement with p a spline on the shaft.As best shown in Fig. 4 the gearing. 52-53 and -55 and the short shaft54 are inclosed by a housing 58 which is width to permit of the freesliding therein of that portion of the housing that encloses the spiralgears 55 and 55. The inclined splined shaft is driven by a suitablemotor 58 (see Figs. 1 and 2), such motor being, in the constructionshown, anair-driven one. I

The rotary cutter-head that has been referred tois indicated by 54 andits faceand the acting edges ofthe removable knives carried thereby areconcave in shape to approximately conform to the curvature of the logsections that the cutter-head acts upon. ,The cutter-head is suitablyjournalled. in bearings 55 formed with the depending arms of a hanger.62 and such hanger also acts to support, opposite one end of thecutter-head, an electric motor 53 which by suitable connection of itsshaft with the cutter-head rotates the same. Extending upwardly from thelongitudinal central portion of the hanger 82 and rigidly bolted theretois a short shaft 6| journalled in a sleeve bearing 5| that, as hereshown, is formed'in a heavy bracket 5|? integral with and extending outfrom one face of the ring-like support 48. At that end of thehanger 52adjacent to the motor 58 the hanger is so formed as to provide anupturnedlip .66, the inner. face of which is curved and bears againstthe edge of a correspondingly-curved short section of a flange. orrib,68 that projectsslightly from the lower part of the bracket 5,|--such To permitthe housed gearing to" also aids in preventing any suchsagging.

Among the adjustments that are required to be 3 end with the undersurface of the bracket 5| given from time to time to the cutter-head isone thatwill so position it that it will extend diagonally across asection of log that is to be barked.

Referring'now to such adjusting means,--59"indic'ates a bracket carriedby, and preferably in- I ,jects fromth'e same face as-the bracket=5| andtegral with, the ring-like member 48.

is adjacentlto one end of said last-named bracket,'and "mounted upon itand suitably secured theretois a reversible electric motor 18. Uponapro'jectingend portion of the motor shaft is secured'a'gear H which isin mesh with a materially larger gear '12, both of such gears beingenclosed in a housing I3. The short shaft 15 of this gear 12 isconnected. in the construc-.

tion shown, by a universal joint witha threaded shaft 'I4fthat at itsother end passes through and has threaded engagement with a freelyturning nut I8 fitted into the outer end of a lever 11 that retains saidshaft and the parts carried thereby inoperative position.

, projects from and is keyedto the upper end of As before stated theknives carried by the cutcurved to conform to the curvature of thecutterheads surface, and, as-indicat'ed by dotted lines in Fig. 5, eachknife is preferably made in two halves or sections, but, of course, maybe made continuous from end' to end. The kniv:s are indicated by88.

Rigidly secured to the lower or flanged portion' of the sleeve bearing5| (see'Fig. 5) is the lower metal end portion 8| of an ordinary exhaustpipe, the part82, shown as connected to the part 8|,

being preferably of flexible "material to permit free movement of thepart 8| whenever a rotative adjustment of the ring-like member 48issmade.

At 83 is shown a member termed a chip breaker.- It is ,slidablymounted'at its ends to the hanger 52 in such position relative to thecutter-head as to leave an opening 85 of any predetermined size, and insuch position relative to the lower openend of the exhaust pipe as tocommunicate at all times therewith and thereby constitute, in effect, apart of such exhaust. The opening is to be parallel with and conform inshape to the curved face of the cutter-head. Thus a clear and fullexhaust is maintained at all times.

. Turning now to the means by which the various movements of the machineare controlled,-

81 and 88 indicate two levers arranged in close proximity to each other,each being pivotally mounted,'in the construction shown, at .88 uponsuch motors, as they are-to be of any well known construction, nor hasit been considered necessary toencumb'er the several figures ofthedrawings with the power-carrying connections that extend to suchmotors.In Fig. 9, howevenhas been diagrammatically illustrated such parts.Referring very briefly to the showing-there made,

' controlthe admission of compressed air to'said' 4 i so indicates adouble-throw switch mounted upon the hand lever 81, and mounted upon theother hand lever 88 is a similar'switch 92. These switch mechanisms areadapted to be controlled through bell-crank levers SI and 93mouhtedrespectivel'y, onthe large handlevzrs 81,88, 'At' 9| is indlcated a drivechain fordriving'the'countershaft 30. said chain beingdriven by an electric motor 99. The circuits that lead to the electricmotors are shown butnot designatedbyreference numeralsas thatdocs notappear necessary but at I00 is indicated the circuit that leads to thedynamo from which therequired power isiderived,

and at I0! is indicated afswitch that controls the current to the motor.and which may be operated by any suitable means.

With respect to the control oi'thejtwo inotors 41 and ia'thediagramshows connecting rods and 95 pivotally' attached, respectively, to the jlarge hand'levers '81 and", and adapted, as will be understood, toopenand close the valves that last-mentioned motors. v V

While the op zrations of the various elements of themachine have beenstated in connection with the description of their construction andrelative arrangement a brief statement of the operation of the'apparatusas a whole and the advantages derived therefrom is deemed advisable. I

Upon the inclined rolls 25, 25 on the receiving unit 2| of theimachinewill be successively deposited by any suitable means log sections whichmaybe of any of the shapes indicated in Figs.

'10 and 11 and indicated by the reference letters The log sections willbe-so de-' v rolls wzre so arranged as to presentlthe bark sur- .facemore largely uppermost as in that case quite a bit of thebark surfacewould extend down on that side of the log that was farthest from him.Through the operation of the motor 99 that drives the countershaft 30irom'which power is taken to drive the inclined rolls the operator canregulate the rapidity of movement of the log sections and can, when inhis judgment it is necessary or desirable-cause the rolls to be given areverse movement so as to retract a log section in order to be subjectedto a further operation by the cutter- Asthe log sections vary in sizeand shape it is essential that the cutter-head be readily adjustabletoaccommodate it to thevarying conditions. In the first place it must bequickly movable toward and fromtheline oftravel of the log sections, andthis is 'a ccornplished'by so actuating the airmotor 41 as to cause asliding movement, of the cross-head member 42 and its attached parts andthus position the cutter-head farther from or in contact with the logsection to be operated upon. Again, if the log section be from a log ofrather small diameterso thatthe curvature of the barK surf'a cev thereonwill not conform, even approximately, to the curvature of thecutter-head and its knife edges then it would not be feasible to bringthe cutter-head down in v because contact-of the knives with the logwould result in, the removal of a comparatively narrow "strip of bark orthe cutti'ng away-and 'lossot quite an amount of-t-he solid wood. Toavoidthis a position atright angles. tothe log,

disastrous resulttheattendant, by causing the motor Ill tofunction, can"so turn the lever'll. as to causea lateral turning of the cutter-head,

through the movable elements connected there with and hereinbeforedescribed, that will cause it to be presented to the log sectiondiago'nallyto the line of travel of such section-sis for example asshown inFlgJ13-so that its concave face and v the correspondingly shapedcutting edges of the knives will conform very closely to the curvatureof the bark surface and therefore be enabled to remove the bark with but'little, if any, cutting away of the solidwood. Another and veryimportant adjustment of the cutter-head is that which is accomplished bythe rotative movement'of the ring-like member 48 through the actionofthe air motor 5B and the gear mechanism connected therewith ashereinbefore described. The adjustment through these means so moves thecutter-head, which is con-,. nected with the member 48 as described,that it v will move in a plane at right angles. to the line of travel ofthe log sections and hence can be brought into operative engagement withthat;

portion of the bark surface that is at and adjacent to the lowermostedge ofthe log section. By this, however,'it is not to be understoodthat this last mentioned adjustment of the cutter-head must so positionit that it will operatively engage only the lateral portion of the logsection. On:

the contrary, owing to the fact that the three adjustments are madeindependently of each other the cutter-head can be given'this lastdescribed adjustment and can also be given the adjustment that carriesit to'a'position diagonally across the log section so as to make itscurved surface conformto the whole of the bark surface as describedabove. r The relative arrangement of the driven toothed rolls so thatthe log sections are kept canted laterally to present their barksurfaces to the view of the attendant-and the independent adjustments ofthe cutter-head to adapt itsoperation to the constantly varyingconditions in work of this'description are features that combine toproduce cheap, rapid and thorough barking of log sections. v

What we claim as new and desire to secure by Letters Patent'is asfollows: 1. In a machine of the class described, th combination withmeans for supporting andlongitudinally moving a log section, of acutter-head located above the path of travel of said log saidcutter-head to be bodily moved in a plane at right angles to the saidpath of t'ravel'of the log section. 1 v

- In a machine of the class described, the-cornbination with meansforjsupporting and Ilongitudinally 'moving' a log section, 'of' acutter-head having a concave surface, afrotatable'annular member withwhich said cutter-head is connected, a diagonally-movable support onwhich said outter-head is rotatably mounted, means for adjusting saidsupport to move said cutter-head toward or away from the log section tobe operated upon, means for rotating said annular member to cause saidcutter-head to be bodily moved in a plane at right angles to the path oftravel of the log section to bring said cutter-head into operativeengagement with a side portion of said section, and other means foradjusting the cutterhead to conform approximately to the curved surfaceof said log section.

3. In a machine of the class described, the com- ,bination with meansfor supporting and longitudinally moving a log section, of a cutter-headhaving a concave surface, a rotatable annular member with which saidcutter-head is connected, a diagonally-movable support on which saidoutter-head is rotatably mounted, means for adjusting said support tomove said cutter-head toward or away from the log section to be operatedupon, means for rotating said annular member to cause said cutter-headto be bodily moved in a plane at right angles to the path of travel ofthe log section to bring said cutter-head into operative engagement witha sideportion of said section, and other means for adjusting thecutter-head to conform approximately to the curved surface of said logsection, said last-named means comprising a motor supported from andmovable with said annular member.

4. In a machine of the class. described, the combination with means forsupporting a log section while the same is being moved longitudinally,of a cutter-head located above the path of travel of said log section, arotatable member, means carried by said member for supporting saidcutter-head, said supporting means comprising a bracket in which saidcutter-head is rotatably supported and a shaft afiixed to said bracketand journaled in said rotatable member, means for moving said rotatablesupporting member in a direction to carry the cutter-head toward or awayfrom the said path of travel, means for rotating said supporting member,and other means for rocking said bracket shaft to cause a turning of thecutter-head to a position diagonal to said path of travel of the logsection.

5. In a machine of the class described, the combination with means forsupporting a log section while the same is being moved longitudinally,of a cutter-head located opposite the path of travel of said logsection, a rotatable member, means carried by said member for supportingsaid cutter-head, said supporting means comprising a bracket in whichsaid cutter-head is rotatably supported and a shaft affixed to saidbracket and journaled in said rotatable member, means for movingsaid'ro-tatablesupporting member in a direction to carry the cutter-headtoward or away from said path of travel, means for rotating saidsupporting member, and other means for rocking said bracket shaft tocause a turning of the cutter-head to a position diagonal to said pathof travel of the log section, said last-named means comprising a motorsupported from and movable with said annular mem ber and including alsomechanism interposed between and connecting the shaft of said motor withsaid bracket shaft.

6. In a machine of the class described, the combination of two alignedseparated units, a

plurality of inclined toothed rollers supported by each of such units,said rollers of each unit forming a trough-like support and moving meansfor a section that has been severed lengthwise from a log, the rollersthat constitute one side of such trough projecting at a differentinclination from those at the other side whereby a log section restingon and moved by said rollers will be tilted laterally to present more ofits bark surface toward one side of the machine, means for driving allof said toothed rollers synchronously, a stationary element located inthe space between said units and projecting to a considerable distanceabove the said trough-like;

support, a cutter-head, and means carried by said stationary element forsupporting said outter-head,

7. In a machine of the class described, the combination of a supportingframe, a plurality of inclined toothed rollers mounted upon said frame,said rollers being arranged to form a trough-like support for a sectionthat has been severed lengthwise from a log, the rollers that constituteone side of such trough projecting at a different-inclination from thosethat constitute the other side, whereby a log section resting on saidrollers will be tilted laterally to present more of its mark surfacetoward one side of the machine, means for driving all of said toothedrollers synchronously, a stationary element located opposite an'endportion of said supporting frame and projecting to a considerabledistance away from such trough-like support, a cutterhead, and meanscarried by said stationary element for movably supporting saidcutter-head, said stationary element being located and arranged topermit the passage past it of the log section after such section hasbeen acted upon by the cutter-head. I

8. Ina machine of the class described, the combination of means forsustaining in a laterally-tilted position a section that has beensevered lengthwise from a log, a cutter-head, three separate means foreffecting adjustments of the cutter-head with respect to the logsection, one 01 such adjustments being toward and from the section, asecond adjustment being in a plane at right angles to the path of travelof the section, and the third adjustment being to a position diagonal tosaid line of travel, and independently-controlled means for operatingeach of such adjusting means separately or operating either of the twolast-named adjusting means simultaneously with the first-named means.

9. In a machine of the class described, the combination with means forsupporting and longitudinally moving a log section, of a cutterheadlocated opposite a bark-covered surface of said leg section, threeseparate means for effecting adjustments of the cutter-head with respectto the log section, one of such adjustments being toward and away fromthe section, a second adjustment being to position it in a plane atright angles to thepath of travel of the section,

FREDERICK A. NICHOLSON. WlLMOT T. PRITCHARD.

